This invention relates to a charging generator for a motor vehicle, and more particularly to improvements in a sealing structure disposed around a brush holder and associated slip rings included in such a generator.
A conventional sealing structure of the type referred to has comprised a cylindrical cover extending axially inwardly of a charging generator from a rear bracket thereof, at least two slip rings disposed coaxially within the cover, and a brush holder including one end portion inserted into an axial opening disposed in the cover to form a narrow gap between the same and the adjacent side wall of the opening and at least two spring loaded brushes housed in the brush holder to slidably contact the slip ring respectively. The brush holder has included a pair of protrusions running along the outer periphery of the cover to form therebetween another narrow gap which communitates with the firstmentioned narrow gap to form a labyrinth between the brush holder and the cover whereby muddy water and dirt are prevented from entering the interior of the cover.
Lately salt is frequently sprinkled on roads to prevent the roads from freezing. The resulting brine has entered the inside of the cover through the abovementioned labyrinth. This has meant that conventional sealing structures such as described above do not have a satisfactory sealing function.
Accordingly it is an object of the present invention to provide a charging generator for a motor vehicle having an improved sealing structure constructed at an extremely low cost.